Stacking penalties.

Seems stupid, and I think it is, but that is how it goes.

Not sure if it applies to active hardeners as well, but I suspect it does.

- Each additional reduction bonus (resistance for example) has lesser effect, even without any balancing penalties

10% damage reduction = 0.9 x damage taken
15% damage reduction = 0.85 x damage taken

0.9 * 0.85 = 0.765 = 23.5% damage reduction

Can someone who uses a tank tell me if the resistance figures here (in column E) are accurate?

As his math correctly identifies additional damage reduction only reduces damage by the amount of remaining damage you are taking. This is done in EVE such that simply adding 4x 40% damage reduction doesn't give you 100% resist.

It's rather unique to damage resistances, and helps to ensure a natural stacking penalty.

that is, applying the bigger penalty to the higher resist plate.

Aqil, one more test case: With 10% damage reduction from skills, a 15% module, and a 10% module, the game shows 29.56% as my final resists.

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So given your calculation we can recover the 23.5%. Now there's other situations I still cannot calculate.
New scenario: 2x 15% resistance plates, plus standard 10%, is listed as 33.47% in game.

If I do each plate separately, taking 10%, then 15% of the remaining, then 15% of the remaining, I get 34.975% (order doesn't matter). This is higher than 33.47%, of course :)

If I calculate the 15% as a resist on the remaining 0.9 after applying 10% damage reduction, it gives 13.5%. If I then add these together using the stacking penalty, it comes up with a total resist of 25.77%. This gives a final resist of 33.19%. Closer to 33.47%, but still not correct.

So not quite sure how to deal with situations where there are multiple resistance modules.
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Resistances or anything which are given for skills shouldnt have stacking penalties

So with shield core skills you get 10% resistance for lvl5 and the same with caladri logi LAV skill so in total you should have 20% off the bat

Then if you add a passive resistance mod then its 35% then the 2nd mod will have stacking penalities because its a mod

Thats how it should work tbh

Ok, as I don't have access to games resistance results, I checked your value of 10%skill and 2x 15% res mod ==> 33,47% res

I tested with stacking penalty values from http://www.eve-wiki.net/index.php?title=Stacking_penalty

and found out that:

Base: 10% skill = 1-0,10 = 0,90
1st 15% res mod = 1-0,15 = 0,85
2nd 15% res mod WITH stacking penalty = (1- 0,15*0,87) = 0,8695

All those multiplied are
0,6651675
and
1-0,6651675 = 33,48325% resistance after skill, unpenalised mod and first penalised mod


This is so close to value (33,47%) you reported it is possible that it's some rounding issue.

Yep, that one works correct, as you can see from the preceding conversation. There is a problem with a scenario where you have 1x15% and 1x10%, as discussed above.

I've looked through the thread and I don't know what problem you're talking but I'm going to infer that it has to do with the order the values are calculated when using modules with varying bonuses. It's always done in whatever order will yield the maximum total bonus.

If using a 15% reduction module and a 10% reduction module the penalty should apply to the 10%.

Correct. That's my understanding of how it should be, too. But in order to obtain the value that is shown in game for me, you would have to apply the penalty to the 15% rather than 10% module. So that's the bug -- it appears the penalty is applied to the wrong module.

But it may be a display bug, an actual bug in resistances, or working as intended (contrary to the way it normally works for other modules).

Skills bonus should not count as a module, they should be implied in your basic resistance.

He was saying that a 10% (skill bonus) + 15% (module bonus) become a 23.5% resistance, if the game not count the 10% as module, why is there the stacking penalty on the 15% module?